Henby selichman



N0. 342,468. Patented May 25, 1886.

WITNESSES %/MZ 7745 'VE NTOI? S Phm-Lum n mr. Wmn lon. 0. C1.

UNITED STATES PATENT OFFICE.

HENRY SELIGMAN, OF IRVINGTON ON-HUDSON, NEW" YORK.

CONDUCTOR FOR MECHANICAL TELEPHONES.

Application filed June 22, 1885.

T0 aZZ whom it may concern.-

Be it known that I, HENRY SELIGMAN, a citizen of the United States, residing at Irving ton-oirHudson, county of \Vestehester, and State of New York, have invented a new and useful Conductor especially adapted for Telephone-Lines, of which the following is a specilication.

My invention consists in connecting the diaphragms of two telephoneinstruments with ametallic conductor made up of a number of wires braided or twisted together in any suitable manner, and overlaying them with a fibrous or other suitable covering material in such a manner that the conduct0r,when completed,will be entirely enveloped, and all the wires will be unexposed. Theselayers of wire which make up the conductor are bars and noninsulated from each other, and are adapted to coact and operate in unison, thereby increasing the molecular disturbance, so that the vibratory effect upon the receivingdiaphragm will be much greater, and therefore more satisfactory, than where a single wire is employed.

The object of placing the covering material upon the exterior of the assemblage of wires is to provide a means for excluding all exterior sounds and disturbances along the line, thereby preventing said exterior noises being reproduced upon the diaphragm, a resultwhich always follows to a greater or less extent where an uncovered conductor is employed.

Referring to the accompanying drawings,

. Figure 1 represents one of these conductors having a portion of the insulating material cut away to show the wires inside, and Fig. 2 is a view of two telephone-instruments connected by my improved conductor.

In these drawings, A represents the wires or CO1](lUOtOl,Wl1lOlJ may bebraided through each other or coiled around each other, oral-ranged together in any other suitable manner, and surrounding these is placed the covering material B, preferably fibrous in its nature, although other suitable materials may be employed. O D are the diaphragms of the transmitting and receiving instruments, respectively. The result ofthis arrangement will be, as aforestated, to produce much better results than heretofore obtained in acoustic or mechanical telephony,.to which thisinvention is more particularly applied. Not only will the ZCZPZCATION forming part of Letters Patent No. 342,468, dated May 25, 1886.

Serial No. 169,408. (No model.)

disagreeable ringing noises be eliminated by employing a number of wires interbraided or twisted together, but the covering material serves to exclude all foreign sounds, and permits the metallic conducting-wires to receive and transmit only such vibratory effects as are received upon the diaphragms of t11e in struments.

Iain aware that the devices going to make up my improved mechanical telephone are severally old and well known. The use of braided or twisted wires, whether for electrical or mechanical telephones, has been before suggested. Insulating coverings for eithersingle or multiple wires have been employed on elec trical conductors, and partially insulating or deadening devices have been also employed on a wire connecting the diaphragms of mechanical telephones. None of these devices will, however, singly accomplish the purpose of the present invention. If the conduetor,whether single or multiple, uniting the diaphragms of a mechanical telephone is left entirely bare,it is affected not only by shocks imparted or by rubbing againstits supports, butby the slightest breeze passing over it, and the result is the disagreeable roaring sound well known to be a drawback to the receivers of such telephones. If the conductor, consisting of a single wire, be covered with a closefitting envelope similar in character to that employed on electrical conductors, the roaring in the receiver, to be sure, is almost entirely arrested; but at the same time the transi'nitting powers of the conductor are so materially impaired as to render the telephone practically worthless for lines of any considerable length. 'It was this difficulty which led Huston, in his Patent No. 285,269, of the 18th September, 1883, to show and de scribe an insulator for a single-line conductor, consisting of a rubber or fibrous thread so wound on the conductor as to arrest and deaden the vibrations thereof when once imparted, but still not sufficiently covering the conductor to entirely destroy its transmitting properties. As it is,the transmitting properties of such conductor are impaired in exact proportion to the quantity of insulation employed; but it is obvious that, although partially effectual in deadening vibrations of the fere with the impact of outside objects upon theline. Thewindblowingoverthelinewould set up vibrations which could be only partially counteracted, especially on short lines, by the imperfect fibrous covering. The absolute exclusion of outside influences on the line can only be attained by surrounding the conductor with a practically impervious envelope; but, as already remarked, such an envelope could not be employed upon a single-line conductor without materially affecting its efficiency.

I have discovered that a conductor consisting of a number of wires braided or twisted together and covered with a close envelope is not open to this objection. This result I attribute to the fact that,although the envelope touches and deadens the vibrations of the outer bends of the wire,thereis,by reason of the close contact of the various threads making up the conductor, a practically continuous inner wire free to vibrate within a metallic and not a deadening envelope.

Although braided ortwisted wires have been before used for electrical telephones, it is well known that the conductors of such telephones do not connect the diaphragm thereof directly and mechanically. There could therefore in such use be no suggestion of the new utility which would accruefrom the applying of such conductors to a mechanical telephone.

The j oi n'ing of the two old elementsnamely, mechanical telephone diaphragms and insulated multiple c0nductorsis with the production of a new and useful result, as abovespecified, and is what I desire to claim herein.

I claim- In combination with the receiving and transmittinginstruments of a mechanical telephone, a multipleconductor uniting said instruments, consisting of a number of wires braided or twisted together and aclose jacket or envelope surrounding said wires, so as to exclude outside influences, while notinterfering with the transmission of speech, substantially as set forth.

HENRY SELIGMAN.

Witnesses:

HERBERT KNIGHT, WM. H. OAPEL. 

